Hack/Slash is an ongoing comic book series, launched from several one shots of the same name, published by Image Comics (previously by Devil's Due Publishing). The series, starting as a series of one-shots, was created by writer and sometime penciller Tim Seeley. The focus of the series is on a horror victim, Cassie, who strikes back at the monsters, known as "slashers", with Vlad, a disfigured "gentle giant" who frequently wears a gas mask.

The property started in 2004 as a series of one-shots, starting with the Stefano Caselli-penciled Hack/Slash (later referred to by its story title Euthanized), followed by the Federica Manfredi-penciled Girls Gone Dead.

2005 saw the one-shots Comic Book Carnage and the series stars, Vlad and Cassie, appeared in the Aadi Salman penciled The Final Revenge of Evil Ernie. The "Hack/Slash" one shots were collected as the First Cut trade paperback in the same year. The first "Hack/Slash" miniseries debuted, Land of Lost Toys, penciled by Dave Crosland, followed by a collection of new short stories in a 2006 special issue called Trailers (featuring art by writer stefano caselli and Tim Seeley, original penciler Caselli, Mike Norton, Skottie Young and Josh Medors).

A 25-cent preview issue giving newcomers a recap of "Euthanized" hit the markets in 2006, along with "Slice Hard", the first one-shot of 2006. Seeley penciled the new part of the preview and was one of the pencilers and inkers of the one-shot along with Mark Englert, Nate Bellgarde, Andy Kuhn and Joe Largent. The one-shot Hack/Slash Vs. Chucky, had the lead duo taking on the evil doll and was penciled by Matt Merhoff.

2007 had a Free Comic Day tie-in with Devil's Due's "Family Guy", where both books had half the issue to itself. The "Hack/Slash" section had a recap portion of the 25 cent preview issue. "Hack/Slash" graduated to an ongoing series in May 2007.

On March 2010 it was announced at the Emerald City Comincon and then widely across most of the comic world net that creator Tim Seeley was taking his creation Hack/Slash from longtime publishers Devil's Due Publications to a new home at Image Comics. The move comes after much reported news that Devil's Due was going through a lot of financial difficulties with staff on all levels not being paid for months on end and likewise Tim Seeley also not receiving his paycheck and thus not being able to pay his staff of artists and colorists. Hack/Slash's tenure at Devil's Due closed with issue #32 of the then-ongoing series. Hack/Slash's first release on Image was the 4-part miniseries My First Maniac, which was followed by a new Hack/Slash series.

Vlad – The enigmatic partner of Cassie, Vlad is a big, muscular, disfigured man, who wears a gas mask and brandishes two big meat cleavers. Met by Cassie when they were both stalking the "Meatman Killer", Cassie soon befriended him. There's not much known about Vlad, not even his full name, but he seems very aware of his unconventional looks, which prompts him to wear the gas mask (which, he says, protects him from the thin outside air he has been deprived of for 20 years – though he can be seen breathing without his mask too). According to Vlad, he was raised by a butcher who rescued him from a garbage can. The butcher served as his only human contact. He used comic books to teach Vlad to read; he also taught Vlad how to use knives to help him adjust to his deformities. When the butcher died, Vlad was forced to go outside where rumors of the Meat Man started and he eventually met Cassie. Vlad's relationship with Cassie is quite paternal, as Vlad seems utterly concerned with his "little one's" well being. Quite naive, but well-versed in strategy and battle skills, Vlad doubles as the "muscle" of the team, and as a sort of guardian for Cassie, counseling and comforting her when it's needed.

Chris Krank and Doctor Lisa Elsten – Lisa was introduced in Hack/Slash: Euthanized as the girlfriend of Kyle Bell. Chris appeared later in Hack/Slash: Land of Lost Toys #1 as the geeky roommate of Jason Michaels. Both survived the Slasher attacks in their respective stories and because of this reappeared in Hack/Slash vs. Chucky as two of the potential victims of Laura Lochs. They are now in a relationship and living together. Together they have formed Hack/Slash Inc, a website for Slasher survivors.

Margaret Crump aka Georgia Peaches – Georgia is a recurring character in Hack/Slash, who is currently a potential love interest for Cassie. Introduced in Hack/Slash #2 as a stripper who was a fan of the band, Acid Washed. Was sent to the hell dimension of Nef by the band along with Cassie as virgin sacrifices. During their time caged up together, Cassie and Georgia discussed Cassie's lack of a sex life and her orientation, which she is still unsure of. This led to Georgia suggesting that were they not chained up, they could have sex with each other in order to become "impure" and therefore escape. Since escaping from Nef, Cassie and Georgia have been keeping in touch by phoning each other every day. In Hack/Slash #8, Cassie fantasizes about kissing Georgia, suggesting that Georgia's previous suggestion about Cassie being gay may actually be correct. However, after several bad experiences with slashers Cassie breaks away from her to keep her safe. The two would later try to reconnect as lovers, but Georgia this time would move away.

Pooch – Pooch first appears in the "Shout at the Devil" arc as a spawn and servant of the Neflords, H. P. Lovecraft-esque entities which reproduce by impregnating virgins from Earth, whom they have abducted to their dimension of Nef. Resembling a demonic hairless dog, Pooch works under the Neflords' lieutenant Elvis Presley and, after his master is killed and Cassie and Georgia escape Nef, is sent to Earth to kill Cassie, but instead meets and befriends Chris and Lisa, who (reluctantly at first) let Pooch live with them. Pooch decides to abandon the Neflords and have Chris and Lisa as his new masters due to their kindness to him. In the arc "Closer", Pooch is severely injured while defending Chris and Lisa from another agent of the Neflords sent to kill him and Cassie, an agent which is later killed by Chris; Pooch's display of loyalty and bravery ultimately cause Chris and Lisa to realize how much he means to them, and the two have begun helping him to recuperate.

Samhain – Samhain saved Cassie Hack from the Black Lamp Society murder attempt. He has no memory of his past life, except for his exceptional fighting skills and his hatred to the Society. He's trying to rescue Ava Park from the Black Lamp Society with the aid of Cassie and Vlad. Making his debut in issue #20, Samhain is a jack-o-lantern masked ex-slasher. His conscience restored as well as his lack of desire to commit meaningless murder like other slashers. In later issues, Samhain's face is revealed from behind the mask, and following his capture and re-programming by the Black Lamp Society in issues 24-25, he then once again becomes, albeit briefly, the deadliest slasher of all; he is then ordered and obeys in the killing of his love, Dr. Ava Park.

This spell is only broken by a passionate kiss from Cassie which restores his mind back to his former pre-slasher default setting. But for Cassie, this also awakens something inside of her she didn't think possible, and in later issues is found to be deeply fantasizing about and desiring the masked man. Eventually, she and Samhain give into their attraction and have sex.

Slashers (known to the government as "Revenants") are the beings that Cassie and Vlad hunt down. Slashers as a whole can be divided into two broad categories. The first and most common are the undead variety: These are people who died while filled with rage toward life, and somehow return from the dead filled with only that rage driving them to kill. While their exact abilities vary individually, all possess resistance to damage, and must suffer severe bodily harm to be killed. This kind can be controlled by the proper magics, and once their body has been sufficiently destroyed, usually stay dead. The other kind are people who are still alive, but are often insane and engage in Slasher behavior. They can be killed by normal means.

The series has been turned into a stage play "Hack/Slash: Stage Fright", adapting "Euthanized" and "Girls Gone Dead". The play utilizes comic book panel simulation. The series has also been developed into an additional play simply titled "Hack/Slash" with the Strangeloop Theatre and CIC Theater in Chicago, playing from September 12th through November 1st of 2014, adapting various sections from the "Omnibus" to develop a story while directly coordinating with the author of the original content, Tim Seeley.[5]